You can use the "Run configurations..." or "Debug configurations..." menu option to set up your own. See the Eclipse docs for that.
Once you do the above once, the configuration you used previously becomes the default so a simple (and quick) left-click on the toolbar icon will launch the app again.
If you're new to both Java and Eclipse, I suggest doing one of the introductory tutorials on the eclipse.org web site that take you through the process of creating a Java project, adding a few files to it, building it, running it, and debugging it. This will give you the necessary experience with Eclipse and also teach you the basics of Java. Once you've done that you can start another thread with specific questions, if you have any.
Good luck, and thanks for joining us at RPTools.
